# Movable Type (r) Open Source (C) 2001-2011 Six Apart, Ltd.
# This program is distributed under the terms of the
# GNU General Public License, version 2.
#
# $Id$
package MT::CMS::Common;

use strict;

use MT::Util qw( format_ts offset_time_list relative_date remove_html);

sub save {
    my $app  = shift;
    my $q    = $app->param;
    my $type = $q->param('_type');

    return $app->errtrans("Invalid request.")
        unless $type;

    # being a general-purpose method, lets look for a mode handler
    # that is specifically for editing this type. if we find it,
    # reroute to it.

    my $save_mode = 'save_' . $type;
    if ( my $hdlrs = $app->handlers_for_mode($save_mode) ) {
        return $app->forward($save_mode);
    }

    my $id = $q->param('id');
    $q->param( 'allow_pings', 0 )
        if ( $type eq 'category' ) && !defined( $q->param('allow_pings') );

    $app->validate_magic() or return;
    my $author = $app->user;

    # Check permissions
    my $perms = $app->permissions;

    if ( !$author->is_superuser ) {
        if ( ( $type ne 'author' ) && ( $type ne 'template' ) )
        {    # for authors, blog-ctx $perms is not relevant
            return return $app->permission_denied()
                if !$perms && $id;
        }

        $app->run_callbacks( 'cms_save_permission_filter.' . $type,
            $app, $id )
            || return $app->permission_denied();
    }

    my $param = {};
    if ( $type eq 'author' ) {
        if ( my $delim = $q->param('tag_delim') ) {
            $param->{ 'auth_pref_tag_delim_' . $delim } = 1;
            $param->{'auth_pref_tag_delim'} = $delim;
        }
        $param->{languages}
            = MT::I18N::languages_list( $app,
            $q->param('preferred_language') )
            if $q->param('preferred_language');
        $param->{create_personal_weblog}
            = $q->param('create_personal_weblog') ? 1 : 0;
        require MT::Permission;
        my $sys_perms = MT::Permission->perms('system');
        foreach (@$sys_perms) {
            $param->{ 'perm_can_' . $_->[0] } = 1
                if $q->param( 'can_' . $_->[0] );
        }
    }

    my $filter_result
        = $app->run_callbacks( 'cms_save_filter.' . $type, $app );

    if ( !$filter_result ) {
        my %param = (%$param);
        $param{error}       = $app->errstr;
        $param{return_args} = $app->param('return_args');

        if ( ( $app->param('cfg_screen') || '' ) eq 'cfg_prefs' ) {
            return MT::CMS::Blog::cfg_prefs( $app, \%param );
        }
        elsif ( $app->param('forward_list') ) {
            return $app->json_error( $param{error} );
        }
        else {
            if ($type) {
                my $mode = 'view_' . $type;
                if ( $app->handlers_for_mode($mode) ) {
                    return $app->forward( $mode, \%param );
                }
            }
            return $app->forward( 'view', \%param );
        }
    }

    return $app->errtrans(
        'The Template Name and Output File fields are required.')
        if $type eq 'template' && !$q->param('name') && !$q->param('outfile');

    if ( $type eq 'template' ) {

        # check for preview file
        $app->remove_preview_file;

        # check for autosave
        if ( $q->param('_autosave') ) {
            return $app->autosave_object();
        }
    }

    my $class = $app->model($type)
        or return $app->errtrans( "Invalid type [_1]", $type );
    my ($obj);
    if ($id) {
        $obj = $class->load($id)
            or
            return $app->error( $app->translate( "Invalid ID [_1]", $id ) );
    }
    else {
        $obj = $class->new;
    }

    my $original = $obj->clone();
    my $names    = $obj->column_names;
    my %values   = map { $_ => ( scalar $q->param($_) ) } @$names;
    if (   $type eq 'blog'
        && $obj->class eq 'blog'
        && (!$app->param('cfg_screen')
            || ( $app->param('cfg_screen')
                && ( $app->param('cfg_screen') || '' ) eq 'cfg_prefs' )
        )
        )
    {
        unless ( $obj->id ) {
            my $subdomain = $q->param('site_url_subdomain');
            $subdomain = '' if !$q->param('use_subdomain');
            $subdomain .= '.' if $subdomain && $subdomain !~ /\.$/;
            $subdomain =~ s/\.{2,}/\./g;
            my $path = $q->param('site_url_path');
            $values{site_url} = "$subdomain/::/$path";

            $values{site_path} = $app->param('site_path_absolute')
                if $app->param('use_absolute')
                    && $app->param('site_path_absolute');
        }

        unless ( $author->is_superuser
            || ( $perms && $perms->can_do('save_all_settings_for_blog') ) )
        {
            if ( $id && !( $perms->can_do('save_blog_pathinfo') ) ) {
                delete $values{site_url};
                delete $values{site_path};
                delete $values{archive_url};
                delete $values{archive_path};
                delete $values{site_path_absolute}
                    if $values{site_path_absolute};
            }
            if ( $id && !( $perms->can_do('save_blog_config') ) ) {
                delete $values{$_} foreach grep {
                           $_ ne 'site_path'
                        && $_ ne 'site_url'
                        && $_ ne 'archive_path'
                        && $_ ne 'archive_url'
                } @$names;
            }
        }
    }

    if ( $type eq 'website'
        || ( $type eq 'blog' && $obj->class eq 'website' ) )
    {
        unless ( $author->is_superuser
            || ( $perms && $perms->can_do('save_all_settings_for_website') ) )
        {
            if ( $id && !( $perms->can_do('save_blog_pathinfo') ) ) {
                delete $values{site_url};
                delete $values{site_path};
            }
            if ( $id && !( $perms->can_do('save_blog_config') ) ) {
                delete $values{$_}
                    foreach grep { $_ ne 'site_path' && $_ ne 'site_url' }
                    @$names;
            }
        }
    }

    if ( $type eq 'author' ) {

        #FIXME: Legacy columns - remove them
        my @cols
            = qw(is_superuser can_create_blog can_view_log can_edit_templates);
        if ( !$author->is_superuser ) {
            delete $values{$_} for @cols;
        }
        else {
            if ( !$id || ( $author->id != $id ) ) {

                # Assign the auth_type unless it was assigned
                # through the form.
                $obj->auth_type( $app->config->AuthenticationModule )
                    unless $obj->auth_type;
                if ( $values{'status'} == MT::Author::ACTIVE() ) {
                    my $sys_perms = MT::Permission->perms('system');
                    if ( defined( $q->param('can_administer') )
                        && $q->param('can_administer') )
                    {
                        $obj->is_superuser(1);
                    }
                    else {
                        foreach (@$sys_perms) {
                            my $name = 'can_' . $_->[0];
                            if ( defined $q->param($name) ) {
                                $obj->$name( $q->param($name) );
                                delete $values{$name};
                            }
                            else {
                                $obj->$name(0);
                            }
                        }
                    }
                }
            }
        }
        delete $values{'password'};
    }

    if ( $type eq 'blog' || $type eq 'website' ) {

        # If this is a new blog, set the preferences, archive settings
        # and template set to the defaults.
        if ( !$obj->id ) {
            $obj->language( $q->param('blog_language')
                    || MT->config->DefaultLanguage );
            $obj->nofollow_urls(1);
            $obj->follow_auth_links(1);
            $obj->page_layout('layout-wtt');
            my @authenticators = qw( MovableType );
            my @default_auth = split /,/, MT->config('DefaultCommenterAuth');
            foreach my $auth (@default_auth) {
                my $a = MT->commenter_authenticator($auth);
                if ( !defined $a
                    || ( exists $a->{condition} && ( !$a->{condition}->() ) )
                    )
                {
                    next;
                }
                push @authenticators, $auth;
            }
            $obj->commenter_authenticators( join ',', @authenticators );
            require MT::Theme;
            my $theme = MT::Theme->load( $app->param( $type . '_theme' ) )
                or return $app->error('Internal error: Unknown theme!');
            $obj->theme_id( $theme->{id} );
        }

        if ( $values{file_extension} ) {
            $values{file_extension} =~ s/^\.*//
                if ( $q->param('file_extension') || '' ) ne '';
        }

        unless ( $values{site_url} =~ m!/$! ) {
            my $url = $values{site_url};
            $values{site_url} = $url;
        }
    }

    if ( $type eq 'entry' || $type eq 'page' ) {

        # This has to happen prior to callbacks since callbacks may
        # be affected by the translation...

        # translates naughty words when PublishCharset is NOT UTF-8
        $app->_translate_naughty_words($obj);
    }

    if ( $type eq 'template' ) {
        if (   $q->param('type') eq 'archive'
            && $q->param('archive_type') )
        {
            $values{type} = $q->param('archive_type');
        }
    }

    if ( $type eq 'notification' ) {
        if ( defined $obj->blog_id ) {
            delete $values{'blog_id'};
        }
    }

    delete $values{'id'} if exists( $values{'id'} ) && !$values{'id'};
    $obj->set_values( \%values );

    if ( $obj->properties->{audit} ) {
        $obj->created_by( $author->id ) unless $obj->id;
        $obj->modified_by( $author->id ) if $obj->id;
    }

    unless (
        $app->run_callbacks( 'cms_pre_save.' . $type, $app, $obj, $original )
        )
    {
        if ( 'blog' eq $type ) {
            my $meth = $q->param('cfg_screen');
            if ( $meth && $app->handlers_for_mode($meth) ) {
                $app->error(
                    $app->translate( "Save failed: [_1]", $app->errstr ) );
                return $app->$meth;
            }
        }
        $param->{return_args} = $app->param('return_args');
        return edit(
            $app,
            {   %$param,
                error => $app->translate( "Save failed: [_1]", $app->errstr )
            }
        );
    }

    # Done pre-processing the record-to-be-saved; now save it.

    $obj->touch() if ( $type eq 'blog' || $type eq 'website' );

    $obj->save
        or return $app->error(
        $app->translate( "Saving object failed: [_1]", $obj->errstr ) );

    # Now post-process it.
    $app->run_callbacks( 'cms_post_save.' . $type, $app, $obj, $original )
        or return $app->error( $app->errstr() );

    # Save NWC settings and revision settings
    my $screen = $q->param('cfg_screen') || '';
    if ( ( $type eq 'blog' || $type eq 'website' ) && $screen eq 'cfg_entry' )
    {
        my @fields;
        push( @fields, 'title' )     if $q->param('nwc_title');
        push( @fields, 'text' )      if $q->param('nwc_text');
        push( @fields, 'text_more' ) if $q->param('nwc_text_more');
        push( @fields, 'keywords' )  if $q->param('nwc_keywords');
        push( @fields, 'excerpt' )   if $q->param('nwc_excerpt');
        push( @fields, 'tags' )      if $q->param('nwc_tags');
        my $fields = @fields ? join( ',', @fields ) : 0;
        $obj->smart_replace_fields($fields);
        $obj->smart_replace( $q->param('nwc_smart_replace') );
        $obj->save;
    }

    # Finally, decide where to go next, depending on the object type.
    my $blog_id = $q->param('blog_id');
    if ( $type eq 'blog' || $type eq 'website' ) {
        $blog_id = $obj->id;
    }

    # if we are saving/publishing a template, make sure to log on activity log
    if ( $type eq 'template' ) {
        my $blog = $app->model('blog')->load( $obj->blog_id );
        if ($blog) {
            $app->log(
                {   message => $app->translate(
                        "'[_1]' edited the template '[_2]' in the blog '[_3]'",
                        $app->user->name, $obj->name, $blog->name
                    ),
                    level    => MT::Log::INFO(),
                    blog_id  => $blog->id,
                    class    => 'template',
                    category => 'edit',
                }
            );
        }
        else {
            $app->log(
                {   message => $app->translate(
                        "'[_1]' edited the global template '[_2]'",
                        $app->user->name, $obj->name
                    ),
                    level    => MT::Log::INFO(),
                    class    => 'template',
                    category => 'edit',
                }
            );
        }
    }

    # TODO: convert this to use $app->call_return();
    # then templates can determine the page flow.
    if ( my $cfg_screen = $q->param('cfg_screen') ) {
        if ( $cfg_screen eq 'cfg_publish_profile' ) {
            my $dcty = $obj->custom_dynamic_templates || 'none';
            if ( ( $dcty eq 'all' ) || ( $dcty eq 'archives' ) ) {
                require MT::CMS::Blog;
                my %param = ();
                MT::CMS::Blog::_create_build_order( $app, $obj, \%param );
                $q->param( 'single_template', 1 );  # to show tmpl full-screen
                if ( $dcty eq 'all' ) {
                    $q->param( 'type', $param{build_order} );
                }
                elsif ( $dcty eq 'archives' ) {
                    my @ats = map { $_->{archive_type} }
                        @{ $param{archive_type_loop} };
                    $q->param( 'type', join( ',', @ats ) );
                }
                return MT::CMS::Blog::start_rebuild_pages($app);
            }
        }
        if ( $cfg_screen eq 'cfg_templatemaps' ) {
            $cfg_screen = 'cfg_prefs';
        }
        my $site_path = $obj->site_path;
        my $fmgr      = $obj->file_mgr;
        unless ( $fmgr->exists($site_path) ) {
            $fmgr->mkpath($site_path);
        }
        $app->add_return_arg( no_writedir => 1 )
            unless $fmgr->exists($site_path) && $fmgr->can_write($site_path);
    }
    elsif ( $type eq 'template' && $q->param('rebuild') ) {
        if ( !$id ) {

            # add return argument for newly created templates
            $app->add_return_arg( id => $obj->id );
        }
        if ( $obj->build_type ) {
            if ( $obj->type eq 'index' ) {
                $q->param( 'type',            'index-' . $obj->id );
                $q->param( 'tmpl_id',         $obj->id );
                $q->param( 'single_template', 1 );
                return $app->forward('start_rebuild');
            }
            else {

                # archive rebuild support
                $q->param( 'id',     $obj->id );
                $q->param( 'reedit', $obj->id );
                return $app->forward('publish_archive_templates');
            }
        }
    }
    elsif ( $type eq 'template' ) {
        if (   $obj->type eq 'archive'
            || $obj->type eq 'category'
            || $obj->type eq 'page'
            || $obj->type eq 'individual' )
        {
            my $static_maps = delete $app->{static_dynamic_maps};
            require MT::TemplateMap;
            my $terms = {};
            if ( $static_maps && @$static_maps ) {
                $terms->{id} = $static_maps;
            }
            else {

                # all existing maps have been dynamic
                # do nothing
            }
            if (%$terms) {
                my @maps = MT::TemplateMap->load($terms);
                my @ats = map { $_->archive_type } @maps;
                if ( $#ats >= 0 ) {
                    $q->param( 'type', join( ',', @ats ) );
                    $q->param( 'with_indexes',    1 );
                    $q->param( 'no_static',       1 );
                    $q->param( 'template_id',     $obj->id );
                    $q->param( 'single_template', 1 );
                    require MT::CMS::Blog;
                    return MT::CMS::Blog::start_rebuild_pages($app);
                }
            }
        }
    }
    elsif ( $type eq 'blog' || $type eq 'website' ) {
        return $app->redirect(
            $app->uri(
                'mode' => 'cfg_prefs',
                args   => { blog_id => $blog_id, saved => 1 }
            )
        );
    }
    elsif ( $type eq 'author' ) {

        # Delete the author's userpic thumb (if any); it'll be regenerated.
        if (   $original->userpic_asset_id
            && $original->userpic_asset_id != $obj->userpic_asset_id )
        {
            my $thumb_file = $original->userpic_file();
            my $fmgr       = MT::FileMgr->new('Local');
            if ( $fmgr->exists($thumb_file) ) {
                $fmgr->delete($thumb_file);
            }
        }
    }

    if ( $app->param('forward_list') ) {
        return $app->forward('filtered_list');
    }

    $app->add_return_arg( 'id' => $obj->id ) if !$original->id;
    $app->add_return_arg( 'saved' => 1 );
    $app->call_return;
}

sub edit {
    my $app  = shift;

    my $q    = $app->param;
    my $type = $q->param('_type');

    return $app->errtrans("Invalid request.")
        unless $type;

    # being a general-purpose method, lets look for a mode handler
    # that is specifically for editing this type. if we find it,
    # reroute to it.

    my $edit_mode = $app->mode . '_' . $type;
    if ( my $hdlrs = $app->handlers_for_mode($edit_mode) ) {
        return $app->forward( $edit_mode, @_ );
    }

    my %param = eval { $_[0] ? %{ $_[0] } : (); };
    die Carp::longmess if $@;
    my $class = $app->model($type) or return;
    my $blog_id = $q->param('blog_id');

    if ( defined($blog_id) && $blog_id ) {
        return $app->error( $app->translate("Invalid parameter") )
            unless ( $blog_id =~ m/\d+/ );
    }

    $app->remove_preview_file;

    if ( $q->param('_recover') ) {
        my $sess_obj = $app->autosave_session_obj;
        if ($sess_obj) {
            my $data = $sess_obj->thaw_data;
            if ($data) {
                $q->param( $_, $data->{$_} ) for keys %$data;
                $app->delete_param('id')
                    if defined $q->param('id') && !$q->param('id');
                $param{'recovered_object'} = 1;
            }
            else {
                $param{'recovered_failed'} = 1;
            }
        }
        else {
            $param{'recovered_failed'} = 1;
        }
    }
    elsif ( $q->param('qp') ) {
        foreach (qw( title text )) {
            my $data = $q->param($_);
            $q->param( $_, $data );
        }
    }

    $param{autosave_frequency} = $app->config->AutoSaveFrequency;

    my $id     = $q->param('id');
    my $perms  = $app->permissions;
    my $author = $app->user;
    my $cfg    = $app->config;
    $param{styles} = '';
    if ( $type eq 'author' ) {
        if ( $perms || $blog_id ) {
            return $app->return_to_dashboard( redirect => 1 );
        }
    }
    else {
        if (( !$perms || !$blog_id )
            && (   $type eq 'entry'
                || $type eq 'page'
                || $type eq 'category'
                || $type eq 'folder'
                || $type eq 'comment'
                || $type eq 'ping' )
            )
        {
            return $app->return_to_dashboard( redirect => 1 );
        }
    }

    my $cols = $class->column_names;
    require MT::Promise;
    my $obj_promise = MT::Promise::delay(
        sub {
            return $class->load($id) || undef;
        }
    );

    if ( !$author->is_superuser ) {
        $app->run_callbacks( 'cms_view_permission_filter.' . $type,
            $app, $id, $obj_promise )
            || return $app->permission_denied();
    }
    my $obj;
    my $blog;
    my $blog_class = $app->model('blog');
    if ($blog_id) {
        $blog = $blog_class->load($blog_id);
    }
    else {
        $blog_id = 0;
    }

    if ($id) {    # object exists, we're just editing it.
         # Stash the object itself so we don't have to keep forcing the promise
        $obj = $obj_promise->force()
            or return $app->error(
            $app->translate(
                "Load failed: [_1]",
                $class->errstr || $app->translate("(no reason given)")
            )
            );

        # Populate the param hash with the object's own values
        for my $col (@$cols) {
            $param{$col}
                = defined $q->param($col) ? $q->param($col) : $obj->$col();
        }

        # Make certain any blog-specific element matches the blog we're
        # dealing with. If not, call shenanigans.
        if (   ( exists $param{blog_id} )
            && ( $blog_id != ( $obj->blog_id || 0 ) ) )
        {
            return $app->return_to_dashboard( redirect => 1 );
        }

        if ( $class->properties->{audit} ) {
            my $creator = MT::Author->load(
                {   id   => $obj->created_by(),
                    type => MT::Author::AUTHOR()
                }
            );
            if ($creator) {
                $param{created_by} = $creator->name;
            }
            else {
                $param{created_by} = $app->translate("(user deleted)");
            }
            if ( my $mod_by = $obj->modified_by() ) {
                my $modified = MT::Author->load(
                    {   id   => $mod_by,
                        type => MT::Author::AUTHOR()
                    }
                );
                if ($modified) {
                    $param{modified_by} = $modified->name;
                }
                else {
                    $param{modified_by} = $app->translate("(user deleted)");
                }

            }

            # Since legacy MT installs will still have a
            # timestamp type for their modified_on fields,
            # we cannot reliably disaply a modified on date
            # by default; we must only show the modification
            # date IF there is also a modified_by value.
            if ( my $ts = $obj->modified_on ) {
                $param{modified_on_ts} = $ts;
                $param{modified_on_formatted}
                    = format_ts( MT::App::CMS::LISTING_DATETIME_FORMAT(),
                    $ts, undef,
                    $app->user ? $app->user->preferred_language : undef );
            }
            if ( my $ts = $obj->created_on ) {
                $param{created_on_ts} = $ts;
                $param{created_on_formatted}
                    = format_ts( MT::App::CMS::LISTING_DATETIME_FORMAT(),
                    $ts, undef,
                    $app->user ? $app->user->preferred_language : undef );
            }
        }

        $param{new_object} = 0;
    }
    else {    # object is new
        $param{new_object} = 1;
        for my $col (@$cols) {
            $param{$col} = $q->param($col);
        }
    }

    if ( $type eq 'website' || $type eq 'blog' ) {
        require MT::Theme;
        my $themes = MT::Theme->load_all_themes;
        $param{theme_loop} = [
            map { { key => $_->{id}, label => $_->label, } }
                grep {
                       !defined $_->{class}
                    || $_->{class} eq 'both'
                    || $_->{class} eq $type
                } values %$themes
        ];
        $param{'master_revision_switch'} = $app->config->TrackRevisions;
    }

    my $res = $app->run_callbacks( 'cms_edit.' . $type, $app, $id, $obj,
        \%param );
    if ( !$res ) {
        return $app->error( $app->callback_errstr() );
    }

    if ( $param{autosave_support} ) {

        # autosave support, but don't bother if we're reediting
        if ( !$app->param('reedit') ) {
            my $sess_obj = $app->autosave_session_obj;
            if ($sess_obj) {
                $param{autosaved_object_exists} = 1;
                $param{autosaved_object_ts}
                    = MT::Util::epoch2ts( $blog, $sess_obj->start );
            }
        }
    }

    if ( ( $q->param('msg') || "" ) eq 'nosuch' ) {
        $param{nosuch} = 1;
    }
    for my $p ( $q->param ) {
        $param{$p} = $q->param($p) if $p =~ /^saved/;
    }
    $param{page_actions} = $app->page_actions( $type, $obj );
    if ( $class->can('class_label') ) {
        $param{object_label} = $class->class_label;
    }
    if ( $class->can('class_label_plural') ) {
        $param{object_label_plural} = $class->class_label_plural;
    }

    my $tmpl_file = $param{output} || "edit_${type}.tmpl";
    $param{object_type}  ||= $type;
    $param{search_label} ||= $class->class_label;
    $param{screen_id}    ||= "edit-$type";
    $param{screen_class} .= " edit-$type";
    return $app->load_tmpl( $tmpl_file, \%param );
}

sub list {
    my $app  = shift;
    my $q    = $app->param;
    my $type = $q->param('_type');
    my $scope
        = $app->blog ? ( $app->blog->is_blog ? 'blog' : 'website' )
        : defined $app->param('blog_id') ? 'system'
        :                                  'user';
    my $blog_id
        = $app->blog
        ? $app->blog->id
        : 0;
    my $list_mode = 'list_' . $type;
    if ( my $hdlrs = $app->handlers_for_mode($list_mode) ) {
        return $app->forward($list_mode);
    }
    my %param;
    $param{list_type} = $type;
    my @messages;

    my @list_components = grep {
               $_->registry( list_properties => $type )
            || $_->registry( listing_screens => $type )
            || $_->registry( list_actions    => $type )
            || $_->registry( content_actions => $type )
            || $_->registry( system_filters  => $type )
    } MT::Component->select;

    my @list_headers;
    push @list_headers,
        File::Spec->catfile( MT->config->TemplatePath, $app->{template_dir},
        'listing', $type . '_list_header.tmpl' );
    for my $c (@list_components) {
        my $f = File::Spec->catfile( $c->path, 'tmpl', 'listing',
            $type . '_list_header.tmpl' );
        push @list_headers, $f if -e $f;
    }

    my $screen_settings = MT->registry( listing_screens => $type )
        or return $app->error(
        $app->translate( 'Unknown action [_1]', $list_mode ) );

    # Condition check
    if ( my $cond = $screen_settings->{condition} ) {
        $cond = MT->handler_to_coderef($cond)
            if 'CODE' ne ref $cond;
        $app->error();
        unless ( $cond->($app) ) {
            if ( $app->errstr ) {
                return $app->error( $app->errstr );
            }
            return $app->return_to_dashboard;
        }
    }

    # Validate scope
    if ( my $view = $screen_settings->{view} ) {
        $view = [$view] unless ref $view;
        my %view = map { $_ => 1 } @$view;
        if ( !$view{$scope} ) {
            return $app->return_to_dashboard( redirect => 1, );
        }
    }

    # Permission check
    if ( defined $screen_settings->{permission}
        && !$app->user->is_superuser() )
    {
        my $list_permission = $screen_settings->{permission};
        my $inherit_blogs   = 1;
        if ( 'HASH' eq ref $list_permission ) {
            $inherit_blogs = $list_permission->{inherit}
                if defined $list_permission->{inherit};
            $list_permission = $list_permission->{permit_action};
        }
        my $allowed  = 0;
        my @act      = split /\s*,\s*/, $list_permission;
        my $blog_ids = undef;
        if ($blog_id) {
            push @$blog_ids, $blog_id;
            if ( $scope eq 'website' && $inherit_blogs ) {
                push @$blog_ids, $_->id foreach @{ $app->blog->blogs() };
            }
        }
        foreach my $p (@act) {
            $allowed = 1, last
                if $app->user->can_do(
                $p,
                at_least_one => 1,
                ( $blog_ids ? ( blog_id => $blog_ids ) : () )
                );
        }
        return $app->permission_denied()
            unless $allowed;
    }

    my $initial_filter;

    my $list_prefs = $app->user->list_prefs         || {};
    my $list_pref  = $list_prefs->{$type}{$blog_id} || {};
    my $rows       = $list_pref->{rows}             || 50; ## FIXME: Hardcoded
    my $last_filter = $list_pref->{last_filter} || '';
    $last_filter = '' if $last_filter eq '_allpass';
    my $last_items = $list_pref->{last_items} || [];
    my $initial_sys_filter = $q->param('filter_key');
    if ( !$initial_sys_filter && $last_filter =~ /\D/ ) {
        $initial_sys_filter = $last_filter;
    }
    $param{ 'limit_' . $rows } = 1;

    require MT::ListProperty;
    my $obj_type   = $screen_settings->{object_type} || $type;
    my $obj_class  = MT->model($obj_type);
    my $list_props = MT::ListProperty->list_properties($type);

    if ( $app->param('no_filter') ) {

        # Nothing to do.
    }
    elsif ( my @cols = $app->param('filter') ) {
        my @vals = $app->param('filter_val');
        my @items;
        my @labels;
        for my $col (@cols) {
            my $val = shift @vals;
            if ( my $prop = $list_props->{$col} ) {
                my ( $args, $label );
                if ( $prop->has('args_via_param') ) {
                    $args = $prop->args_via_param( $app, $val );
                    if ( !$args ) {
                        if ( my $errstr = $prop->errstr ) {
                            push @messages,
                                {
                                cls => 'alert',
                                msg => MT->translate(
                                    q{Invalid filter: [_1]},
                                    MT::Util::encode_html($errstr)
                                )
                                };
                        }
                        next;
                    }
                }
                if ( $prop->has('label_via_param') ) {
                    $label = $prop->label_via_param( $app, $val );
                    if ( !$label ) {
                        if ( my $errstr = $prop->errstr ) {
                            push @messages,
                                {
                                cls => 'alert',
                                msg => MT->translate(
                                    q{Invalid filter: [_1]},
                                    MT::Util::encode_html($errstr),
                                )
                                };
                        }
                        next;
                    }
                }
                push @items,
                    {
                    type => $col,
                    args => ( $args || {} ),
                    };
                push @labels, ( $label || $prop->label );
            }
            else {
                push @messages,
                    {
                    cls => 'alert invalid-filter',
                    msg => MT->translate(
                        q{Invalid filter: [_1]},
                        MT::Util::encode_html($col),
                    )
                    };
            }
        }
        if ( scalar @items ) {
            $initial_filter = {
                label => join( ', ', @labels ),
                items => \@items,
            };
        }
        else {
            $initial_filter = undef;
        }
    }
    elsif ($initial_sys_filter) {
        require MT::CMS::Filter;
        $initial_filter
            = MT::CMS::Filter::filter( $app, $type, $initial_sys_filter );
    }
    elsif ($last_filter) {
        my $filter = MT->model('filter')->load($last_filter);
        $initial_filter = $filter->to_hash if $filter;
    }
    elsif ( scalar @$last_items && $app->param('does_act') ) {
        my $filter = MT->model('filter')->new;
        $filter->set_values(
            {   object_ds => $obj_type,
                items     => $last_items,
                author_id => $app->user->id,
                blog_id   => $blog_id || 0,
                label     => $app->translate('New Filter'),
                can_edit  => 1,
            }
        );
        $initial_filter = $filter->to_hash if $filter;
        $param{open_filter_panel} = 1;
    }

    my $columns = $list_pref->{columns} || [];
    my %cols = map { $_ => 1 } @$columns;

    my $primary_col = $screen_settings->{primary};
    $primary_col ||= [ @{ $screen_settings->{columns} || [] } ]->[0];
    $primary_col = [$primary_col] unless ref $primary_col;
    my %primary_col = map { $_ => 1 } @$primary_col;
    my $default_sort
        = defined( $screen_settings->{default_sort_key} )
        ? $screen_settings->{default_sort_key}
        : '';

    my @list_columns;
    for my $prop ( values %$list_props ) {
        next if !$prop->can_display($scope);
        my $col;
        my $id = $prop->id;
        my $disp = $prop->display || 'optional';
        my $show
            = $disp eq 'force' ? 1
            : $disp eq 'none'  ? 0
            : scalar %cols ? $cols{$id}
            : $disp eq 'default' ? 1
            :                      0;
        my $force   = $disp eq 'force'   ? 1 : 0;
        my $default = $disp eq 'default' ? 1 : 0;
        my @subfields;

        if ( my $subfields = $prop->sub_fields ) {
            for my $sub (@$subfields) {
                push @subfields,
                    {
                    display => $cols{ $id . '.' . $sub->{class} }
                        || $sub->{display} eq 'default',
                    class      => $sub->{class},
                    label      => $app->translate( $sub->{label} ),
                    is_default => $sub->{display} eq 'default' ? 1 : 0,
                    };
            }
        }
        push @list_columns,
            {
            id        => $prop->id,
            type      => $prop->type,
            label     => $prop->label,
            primary   => $primary_col{$id} ? 1 : 0,
            col_class => $prop->col_class,
            sortable  => $prop->can_sort($scope),
            sorted    => $prop->id eq $default_sort ? 1 : 0,
            display   => $show,
            is_default => $force || $default,
            force_display      => $force,
            default_sort_order => $prop->default_sort_order || 'ascend',
            order              => $prop->order,
            sub_fields         => \@subfields,
            };
    }
    @list_columns = sort {
              !$a->{order} ? 1
            : !$b->{order} ? -1
            : $a->{order} <=> $b->{order}
    } @list_columns;

    my @filter_types = map {
        {   prop                  => $_,
            id                    => $_->id,
            type                  => $_->type,
            label                 => $_->filter_label || $_->label,
            field                 => $_->filter_tmpl,
            single_select_options => $_->single_select_options($app),
            verb                  => defined $_->verb ? $_->verb
            : $app->translate('__SELECT_FILTER_VERB'),
            singleton => $_->singleton ? 1
            : $_->has('filter_editable') ? !$_->filter_editable
            : 0,
            editable => $_->has('filter_editable') ? $_->filter_editable : 1,
            base_type => $_->base_type,
        }
        }
        sort {
        ( $a->item_order && $b->item_order )
            ? $a->item_order <=> $b->item_order
            : ( !$a->item_order && $b->item_order )  ? 1
            : ( $a->item_order  && !$b->item_order ) ? -1
            : (
            defined $a->filter_label
            ? ( ref $a->filter_label
                ? $a->filter_label->($screen_settings)
                : $a->filter_label
                )
            : ( ref $a->label ? $a->label->($screen_settings) : $a->label )
            ) cmp(
            defined $b->filter_label
            ? ( ref $b->filter_label
                ? $b->filter_label->($screen_settings)
                : $b->filter_label
                )
            : ( ref $b->label ? $b->label->($screen_settings) : $b->label )
            );
        }
        grep { $_->can_filter($scope) } values %$list_props;

#for my $filter_type ( @filter_types ) {
#    if ( my $options = $filter_type->{single_select_options} ) {
#        require MT::Util;
#        if ( 'ARRAY' ne ref $options ) {
#            $options = MT->handler_to_coderef($options)
#                unless ref $options;
#            $filter_type->{single_select_options} = $options->( $filter_type->{prop} );
#        }
#        for my $option ( @{$filter_type->{single_select_options}} ) {
#            $option->{label} = MT::Util::encode_js($option->{label});
#        }
#    }
#}

    require MT::CMS::Filter;
    my $filters = MT::CMS::Filter::filters( $app, $type, encode_html => 1 );

    my $allpass_filter = {
        label => MT->translate(
            'All [_1]',
            $screen_settings->{object_label_plural}
            ? $screen_settings->{object_label_plural}
            : $obj_class->class_label_plural
        ),
        items    => [],
        id       => '_allpass',
        can_edit => 0,
        can_save => 0,
    };
    $initial_filter = $allpass_filter
        unless $initial_filter;
    ## Encode all HTML in complex structure.
    MT::Util::deep_do(
        $initial_filter,
        sub {
            my $ref = shift;
            $$ref = MT::Util::encode_html($$ref);
        }
    );

    require JSON;
    my $json = JSON->new->utf8(0);

    $param{common_listing}   = 1;
    $param{blog_id}          = $blog_id || '0';
    $param{filters}          = $json->encode($filters);
    $param{initial_filter}   = $json->encode($initial_filter);
    $param{allpass_filter}   = $json->encode($allpass_filter);
    $param{system_messages}  = $json->encode( \@messages );
    $param{filters_raw}      = $filters;
    $param{default_sort_key} = $default_sort;
    $param{list_columns}     = \@list_columns;
    $param{filter_types}     = \@filter_types;
    $param{object_type}      = $type;
    $param{page_title}       = $screen_settings->{screen_label};
    $param{list_headers}     = \@list_headers;
    $param{build_user_menus} = $screen_settings->{has_user_properties};
    $param{use_filters}      = 1;
    $param{use_actions}      = 1;
    $param{object_label}     = $screen_settings->{object_label}
        || $obj_class->class_label;
    $param{object_label_plural}
        = $screen_settings->{object_label_plural}
        ? $screen_settings->{object_label_plural}
        : $obj_class->class_label_plural;
    $param{action_label} = $screen_settings->{action_label}
        if $screen_settings->{action_label};
    $param{action_label_plural} = $screen_settings->{action_label_plural}
        if $screen_settings->{action_label_plural};
    $param{contents_label} = $screen_settings->{contents_label}
        || $obj_class->contents_label;
    $param{contents_label_plural} = $screen_settings->{contents_label_plural}
        || $obj_class->contents_label_plural;
    $param{container_label} = $screen_settings->{container_label}
        || $obj_class->container_label;
    $param{container_label_plural}
        = $screen_settings->{container_label_plural}
        || $obj_class->container_label_plural;
    $param{zero_state}
        = $screen_settings->{zero_state}
        ? $app->translate( $screen_settings->{zero_state} )
        : '',

        my $s_type = $screen_settings->{search_type} || $obj_type;
    if ( my $search_apis = $app->registry( search_apis => $s_type ) ) {
        $param{search_type}  = $s_type;
        $param{search_label} = $search_apis->{label};
    }
    else {
        $param{search_type}  = 'entry';
        $param{search_label} = MT->translate('Entries');
    }

    my $template = $screen_settings->{template} || 'list_common.tmpl';

    my $feed_link = $screen_settings->{feed_link};
    $feed_link = $feed_link->($app)
        if 'CODE' eq ref $feed_link;
    if ($feed_link) {
        $param{feed_url} = $app->make_feed_link( $type,
            $blog_id ? { blog_id => $blog_id } : undef );
        $param{object_type_feed}
            = $screen_settings->{feed_label}
            ? $screen_settings->{feed_label}
            : $app->translate( "[_1] Feed", $obj_class->class_label );
    }

    if ( $param{use_actions} ) {
        $app->load_list_actions( $type, \%param );
        $app->load_content_actions( $type, \%param );
    }

    push @{ $param{debug_panels} },
        {
        name      => 'CommonListing',
        title     => 'CommonListing',
        nav_title => 'CommonListing',
        content =>
            '<pre id="listing-debug-block" style="border: 1px solid #000; background-color: #eee; font-family: Courier;"></pre>',
        }
        if $MT::DebugMode;

    my $tmpl = $app->load_tmpl( $template, \%param )
        or return;
    $app->run_callbacks( 'list_template_param.' . $type,
        $app, $tmpl->param, $tmpl );
    return $tmpl;
}

sub filtered_list {
    my $app              = shift;
    my (%forward_params) = @_;
    my $q                = $app->param;
    my $blog_id          = $q->param('blog_id') || 0;
    my $filter_id        = $q->param('fid') || $forward_params{saved_fid};
    my $blog             = $blog_id ? $app->blog : undef;
    my $scope
        = !$blog         ? 'system'
        : $blog->is_blog ? 'blog'
        :                  'website';
    my $blog_ids
        = !$blog         ? undef
        : $blog->is_blog ? [$blog_id]
        :                  [ $blog->id, map { $_->id } @{ $blog->blogs } ];
    my $debug = {};
    my @messages = @{ $forward_params{messages} || [] };

    if ($MT::DebugMode) {
        require Time::HiRes;
        $debug->{original_prof}      = $Data::ObjectDriver::PROFILE;
        $Data::ObjectDriver::PROFILE = 1;
        $debug->{sections}           = [];
        $debug->{out}                = '';
        $debug->{section}            = sub {
            my ($section) = @_;
            push @{ $debug->{sections} },
                [
                $section,
                Time::HiRes::tv_interval( $debug->{timer} ),
                Data::ObjectDriver->profiler->report_query_frequency(),
                ];
            $debug->{timer} = [ Time::HiRes::gettimeofday() ];
            Data::ObjectDriver->profiler->reset;
        };
        $debug->{print} = sub {
            $debug->{out} .= $_[0] . "\n";
        };
        $debug->{timer} = $debug->{total} = [ Time::HiRes::gettimeofday() ];
        Data::ObjectDriver->profiler->reset;
    }
    else {
        $debug->{section} = sub { };
    }

    my $ds = $q->param('datasource');
    my $setting = MT->registry( listing_screens => $ds )
        or return $app->json_error( $app->translate('Unknown list type') );

    if ( my $cond = $setting->{condition} ) {
        $cond = MT->handler_to_coderef($cond)
            if 'CODE' ne ref $cond;
        $app->error();
        unless ( $cond->($app) ) {
            if ( $app->errstr ) {
                return $app->json_error( $app->errstr );
            }
            return $app->json_error( $app->translate('Invalid request') );
        }
    }

    my $class = $setting->{datasource} || MT->model($ds);
    my $filteritems;
    my $allpass = 0;
    if ( my $items = $q->param('items') ) {
        if ( $items =~ /^".*"$/ ) {
            $items =~ s/^"//;
            $items =~ s/"$//;
            $items = MT::Util::decode_js($items);
        }
        $MT::DebugMode && $debug->{print}->($items);
        require JSON;
        my $json = JSON->new->utf8(0);
        $filteritems = $json->decode($items);
    }
    else {
        $allpass     = 1;
        $filteritems = [];
    }
    require MT::ListProperty;
    my $props = MT::ListProperty->list_properties($ds);
    if ( !$forward_params{validated} ) {
        for my $item (@$filteritems) {
            my $prop = $props->{ $item->{type} };
            if ( $prop->has('validate_item') ) {
                $prop->validate_item($item)
                    or return $app->json_error(
                    MT->translate(
                        'Invalid filter terms: [_1]',
                        $prop->errstr
                    )
                    );
            }
        }
    }

    my $filter = MT->model('filter')->new;
    $filter->set_values(
        {   object_ds => $ds,
            items     => $filteritems,
            author_id => $app->user->id,
            blog_id   => $blog_id || 0,
        }
    );
    my $limit = $q->param('limit') || 50;    # FIXME: hard coded.
    my $page = $q->param('page');
    $page = 1 if !$page || $page =~ /\D/;
    my $offset = ( $page - 1 ) * $limit;

    $MT::DebugMode
        && $debug->{print}->("LIMIT: $limit PAGE: $page OFFSET: $offset");
    $MT::DebugMode && $debug->{section}->('initialize');

    ## FIXME: take identifical column from column defs.
    my $cols = defined( $q->param('columns') ) ? $q->param('columns') : '';
    my @cols = ( '__id', grep {/^[^\.]+$/} split( ',', $cols ) );
    my @subcols = ( '__id', grep {/\./} split( ',', $cols ) );
    $MT::DebugMode && $debug->{print}->("COLUMNS: $cols");

    my $scope_mode = $setting->{scope_mode} || 'wide';
    my @blog_id_term = (
         !$blog_id ? ()
        : $scope_mode eq 'none' ? ()
        : $scope_mode eq 'this' ? ( blog_id => $blog_id )
        : ( blog_id => $blog_ids )
    );

    my %load_options = (
        terms      => {@blog_id_term},
        args       => {},
        sort_by    => $q->param('sort_by') || '',
        sort_order => $q->param('sort_order') || '',
        limit      => $limit,
        offset     => $offset,
        scope      => $scope,
        blog       => $blog,
        blog_id    => $blog_id,
        blog_ids   => $blog_ids,
    );

    my %count_options = (
        terms    => {@blog_id_term},
        args     => {},
        scope    => $scope,
        blog     => $blog,
        blog_id  => $blog_id,
        blog_ids => $blog_ids,
    );

    MT->run_callbacks( 'cms_pre_load_filtered_list.' . $ds,
        $app, $filter, \%count_options, \@cols );

    my $count_result = $filter->count_objects(%count_options);
    if ( !defined $count_result ) {
        return $app->error(
            MT->translate(
                "An error occured while counting objects: [_1]",
                $filter->errstr
            )
        );
    }
    my ( $count, $editable_count ) = @$count_result;

    $MT::DebugMode && $debug->{section}->('count objects');
    $load_options{total} = $count;

    my ( $objs, @data );
    if ($count) {
        MT->run_callbacks( 'cms_pre_load_filtered_list.' . $ds,
            $app, $filter, \%load_options, \@cols );

        $objs = $filter->load_objects(%load_options);
        if ( !defined $objs ) {
            return $app->error(
                MT->translate(
                    "An error occured while loading objects: [_1]",
                    $filter->errstr
                )
            );
        }

        $MT::DebugMode && $debug->{section}->('load objects');

        my %cols = map { $_ => 1 } @cols;
        my @results;

        ## FIXME: would like to build MTML if specified, but currently
        ## many of handlers can't run without blog_id. so commented
        ## out for these codes until the problem would be resolved.
        #my $tmpl;
        #if ( scalar grep { $props->{$_}->has('mtml') } @cols ) {
        #    $tmpl = MT::Template->new;
        #    $tmpl->blog_id($blog_id);
        #    $app->set_default_tmpl_params($tmpl);
        #    $tmpl->context->{__stash}{blog} = $blog;
        #    $tmpl->context->{__stash}{blog_id} = $blog_id;
        #}

        $MT::DebugMode && $debug->{section}->('prepare load cols');
        for my $col (@cols) {
            my $prop = $props->{$col};
            my @result;
            if ( $prop->has('bulk_html') ) {
                @result = $prop->bulk_html( $objs, $app, \%load_options );
            }

            #elsif ( $prop->has('mtml') ) {
            #    for my $obj ( @$objs ) {
            #        $tmpl->context->{__stash}{$ds} = $obj;
            #        my $out = $prop->html($obj, $app);
            #        $tmpl->text($out);
            #        $tmpl->reset_tokens;
            #        $out = $tmpl->output;
            #        push @result, $out;
            #    }
            #}
            elsif ( $prop->has('html') ) {
                for my $obj (@$objs) {
                    push @result, $prop->html( $obj, $app, \%load_options );
                }
            }
            elsif ( $prop->has('html_link') ) {
                for my $obj (@$objs) {
                    my $link = $prop->html_link( $obj, $app, \%load_options );
                    my $raw = MT::Util::encode_html($prop->raw( $obj, $app, \%load_options ));
                    push @result,
                        ( $link ? qq{<a href="$link">$raw</a>} : $raw );
                }
            }
            elsif ( $prop->has('raw') ) {
                for my $obj (@$objs) {
                    my $out = $prop->raw( $obj, $app, \%load_options );
                    push @result, MT::Util::encode_html($out);
                }
            }

            push @results, \@result;
            $MT::DebugMode && $debug->{section}->("prepare col $col");
        }

        for my $i ( 0 .. scalar @$objs - 1 ) {
            push @data, [ map { $_->[$i] } @results ];
        }
    }

    ## Save user list prefs.
    my $list_prefs = $app->user->list_prefs || {};
    my $list_pref = $list_prefs->{$ds}{$blog_id} ||= {};
    $list_pref->{rows} = $limit;
    $list_pref->{columns} = [ split ',', $cols ];
    $list_pref->{last_filter}
        = $filter_id ? $filter_id : $allpass ? '_allpass' : '';
    $list_pref->{last_items} = $filteritems;
    $app->user->list_prefs($list_prefs);
    ## FIXME: should handle errors..
    $app->user->save;

    require MT::CMS::Filter;
    my $filters = MT::CMS::Filter::filters( $app, $ds, encode_html => 1 );

    require POSIX;
    my %res;
    $res{objects}        = \@data;
    $res{columns}        = $cols;
    $res{count}          = $count;
    $res{editable_count} = $editable_count;
    $res{page}           = $page;
    $res{page_max}       = POSIX::ceil( $count / $limit );
    $res{id}             = $filter_id;
    $res{label} = MT::Util::encode_html( $forward_params{saved_label} )
        if $forward_params{saved_label};
    $res{filters}  = $filters;
    $res{messages} = \@messages;
    %res = ( %forward_params, %res );
    $MT::DebugMode && $debug->{section}->('finalize');
    MT->run_callbacks( 'cms_filtered_list_param.' . $ds, $app, \%res, $objs );

    if ($MT::DebugMode) {
        my $total = Time::HiRes::tv_interval( $debug->{total} );
        my $out   = $debug->{out};
        for my $section ( @{ $debug->{sections} } ) {
            $out .= sprintf(
                "%s  : %0.2f ms ( %0.2f %% )\n%s\n",
                $section->[0],
                $section->[1] * 1000,
                $section->[1] / $total * 100,
                $section->[2],
            );
        }
        $out .= sprintf "TOTAL: %0.2f ms\n",    $total * 1000;
        $out .= sprintf "Matched %i Objects\n", $count;
        $res{debug} = $out;
        $Data::ObjectDriver::PROFILE = $debug->{original_prof};
    }
    return $app->json_result( \%res );
}

sub save_list_prefs {
    my $app     = shift;
    my $ds      = $app->param('datasource');
    my $blog_id = $app->param('blog_id') || 0;
    my $blog    = $blog_id ? $app->blog : undef;
    my $scope
        = !$blog         ? 'system'
        : $blog->is_blog ? 'blog'
        :                  'website';
    my $limit      = $app->param('limit')   || 50;    # FIXME: hard coded.
    my $cols       = $app->param('columns') || '';
    my $list_prefs = $app->user->list_prefs || {};
    my $list_pref = $list_prefs->{$ds}{$blog_id} ||= {};
    $list_pref->{rows} = $limit;
    $list_pref->{columns} = [ split ',', $cols ];

#$list_pref->{last_filter} = $filter_id ? $filter_id : $allpass ? '_allpass' : '';
#$list_pref->{last_items} = $filteritems;
    $app->user->list_prefs($list_prefs);
    $app->user->save
        or return $app->json_error( $app->user->errstr );
    return $app->json_result( { success => 1 } );
}

sub delete {
    my $app  = shift;
    my $q    = $app->param;
    my $type = $q->param('_type');

    return $app->errtrans("Invalid request.")
        unless $type;

    return $app->error( $app->translate("Invalid request.") )
        if $app->request_method() ne 'POST';

    # being a general-purpose method, lets look for a mode handler
    # that is specifically for editing this type. if we find it,
    # reroute to it.

    my $delete_mode = 'delete_' . $type;
    if ( my $hdlrs = $app->handlers_for_mode($delete_mode) ) {
        return $app->forward($delete_mode);
    }

    my $parent  = $q->param('parent');
    my $blog_id = $q->param('blog_id');
    my $class   = $app->model($type) or return;
    my $perms   = $app->permissions;
    my $author  = $app->user;

    $app->validate_magic() or return;
    $app->setup_filtered_ids
        if $app->param('all_selected');

    my ( $entry_id, $cat_id, $author_id ) = ( "", "", "" );
    my %rebuild_entries;
    my @rebuild_cats;
    my $required_items = 0;
    my @not_deleted;
    my $delete_count = 0;
    my %return_arg;
    for my $id ( $q->param('id') ) {
        next unless $id;    # avoid 'empty' ids
        if ( ( $type eq 'association' ) && ( $id =~ /PSEUDO-/ ) ) {
            require MT::CMS::User;
            MT::CMS::User::_delete_pseudo_association( $app, $id );
            next;
        }

        my $obj = $class->load($id);
        next unless $obj;
        $app->run_callbacks( 'cms_delete_permission_filter.' . $type,
            $app, $obj )
            || return $app->permission_denied();

        if ( $type eq 'comment' ) {
            $entry_id = $obj->entry_id;
            $rebuild_entries{$entry_id} = 1 if $obj->visible;
        }
        elsif ( $type eq 'ping' || $type eq 'ping_cat' ) {
            require MT::Trackback;
            my $tb = MT::Trackback->load( $obj->tb_id );
            if ($tb) {
                $entry_id = $tb->entry_id;
                $cat_id   = $tb->category_id;
                if ( $obj->visible ) {
                    $rebuild_entries{$entry_id} = 1 if $entry_id;
                    push @rebuild_cats, $cat_id if $cat_id;
                }
            }
        }
        elsif ( $type eq 'tag' ) {

# if we're in a blog context, remove ONLY tags from that weblog
# Also, if we're in a website context, remove ONLY tags from that website and weblog which belongs to website.
            if ($blog_id) {
                my $ot_class = $app->model('objecttag');
                my $blog     = $app->model('blog')->load($blog_id);
                my $iter     = $ot_class->load_iter(
                    {   (   $blog->is_blog
                            ? ( blog_id => $blog_id )
                            : ( blog_id => [
                                    map { $_->id } @{ $blog->blogs }, $blog
                                ]
                            )
                        ),
                        tag_id => $id
                    }
                );

                if ($iter) {
                    my @ot;
                    while ( my $obj = $iter->() ) {
                        push @ot, $obj->id;
                    }
                    foreach (@ot) {
                        my $obj = $ot_class->load($_);
                        next unless $obj;
                        $obj->remove
                            or return $app->errtrans(
                            'Removing tag failed: [_1]',
                            $obj->errstr );
                    }
                }

                $app->run_callbacks( 'cms_post_delete.' . $type, $app, $obj );
                next;

            }
        }
        elsif ( $type eq 'category' ) {
            if ( $app->config('DeleteFilesAtRebuild') ) {
                require MT::Blog;
                require MT::Entry;
                require MT::Placement;
                my $blog = MT::Blog->load($blog_id)
                    or return $app->error(
                    $app->translate( 'Can\'t load blog #[_1].', $blog_id ) );
                my $at = $blog->archive_type;
                if ( $at && $at ne 'None' ) {
                    my @at = split /,/, $at;
                    for my $target (@at) {
                        my $archiver = $app->publisher->archiver($target);
                        next unless $archiver;
                        if ( $archiver->category_based ) {
                            if ( $archiver->date_based ) {
                                my @entries = MT::Entry->load(
                                    { status => MT::Entry::RELEASE() },
                                    {   join => MT::Placement->join_on(
                                            'entry_id',
                                            { category_id => $id },
                                            { unique      => 1 }
                                        )
                                    }
                                );
                                for (@entries) {
                                    $app->publisher
                                        ->remove_entry_archive_file(
                                        Category    => $obj,
                                        ArchiveType => $target,
                                        Entry       => $_
                                        );
                                }
                            }
                            else {
                                $app->publisher->remove_entry_archive_file(
                                    Category    => $obj,
                                    ArchiveType => $target
                                );
                            }
                        }
                    }
                }
            }
        }
        elsif ( $type eq 'page' ) {
            if ( $app->config('DeleteFilesAtRebuild') ) {
                $app->publisher->remove_entry_archive_file(
                    Entry       => $obj,
                    ArchiveType => 'Page'
                );
            }
        }
        elsif ( $type eq 'author' ) {
            if ( $app->config->ExternalUserManagement ) {
                require MT::LDAP;
                my $ldap = MT::LDAP->new
                    or return $app->error(
                    MT->translate(
                        "Loading MT::LDAP failed: [_1].",
                        MT::LDAP->errstr
                    )
                    );
                my $dn = $ldap->get_dn( $obj->name );
                if ($dn) {
                    $return_arg{author_ldap_found} = 1;
                }
            }
        }
        elsif ( $type eq 'website' ) {
            my $blog_class = $app->model('blog');
            my $count = $blog_class->count( { parent_id => $obj->id, } );
            if ( $count > 0 ) {
                push @not_deleted, $obj->id;
                next;
            }
        }

        # FIXME: enumeration of types
        if (   $type eq 'template'
            && $obj->type
            !~ /(custom|index|archive|page|individual|category|widget|backup)/o
            )
        {
            $required_items++;
        }
        else {
            $obj->remove
                or return $app->errtrans(
                'Removing [_1] failed: [_2]',
                $app->translate($type),
                $obj->errstr
                );
            $app->run_callbacks( 'cms_post_delete.' . $type, $app, $obj );
        }
        $delete_count++;
    }

    require MT::Entry;
    for my $entry_id ( keys %rebuild_entries ) {
        my $entry = MT::Entry->load($entry_id);
        $app->rebuild_entry( Entry => $entry, BuildDependencies => 1 )
            or return $app->publish_error();
    }
    for my $cat_id (@rebuild_cats) {

        # FIXME: What about other category-based archives?
        # What if user is not publishing category archives?
        my $cat = MT::Category->load($cat_id);
        $app->rebuild(
            Category    => $cat,
            BlogID      => $blog_id,
            ArchiveType => 'Category'
        ) or return $app->publish_error();
    }
    $app->run_callbacks( 'rebuild', MT::Blog->load($blog_id) );

    if ( $#not_deleted >= 0 ) {
        $return_arg{not_deleted} = 1;
        $return_arg{error_id} = join ',', @not_deleted;
    }
    else {
        $return_arg{
            $type eq 'ping'
            ? 'saved_deleted_ping'
            : 'saved_deleted'
            }
            = 1;
    }

    if ( $q->param('is_power_edit') ) {
        $return_arg{is_power_edit} = 1;
    }
    if ($required_items) {
        $return_arg{error}
            = $app->translate("System templates can not be deleted.");
    }

    if ( $app->param('xhr') ) {
        my @msgs;
        if ( delete $return_arg{saved_deleted} ) {
            push @msgs,
                {
                cls => 'success',
                msg => MT->translate(
                    'The selected [_1] has been deleted from the database.',
                    $delete_count == 1
                    ? $class->class_label
                    : $class->class_label_plural,
                )
                };
        }

        $return_arg{messages} = \@msgs;
        return \%return_arg;
    }
    else {
        $app->add_return_arg(%return_arg);
        return $app->call_return;
    }
}

sub not_junk_test {
    my ( $eh, $app, $obj ) = @_;
    require MT::JunkFilter;
    MT::JunkFilter->filter($obj);
    $obj->is_junk ? 0 : 1;
}

sub build_revision_table {
    my $app = shift;
    my (%args) = @_;

    my $q     = $app->param;
    my $type  = $q->param('_type');
    my $class = $app->model($type);
    my $param = $args{param};
    my $obj   = $args{object};
    my $blog  = $obj->blog || MT::Blog->load( $q->param('blog_id') ) || undef;
    my $lang  = $app->user ? $app->user->preferred_language : undef;

    my $js = $param->{rev_js};
    unless ($js) {
        $js
            = "location.href='"
            . $app->uri
            . '?__mode=view&amp;_type='
            . $type;
        if ( my $id = $obj->id ) {
            $js .= '&amp;id=' . $id;
        }
        if ( defined $blog ) {
            $js .= '&amp;blog_id=' . $blog->id;
        }
    }
    my %users;
    my $hasher = sub {
        my ( $rev, $row ) = @_;
        if ( my $ts = $rev->created_on ) {
            $row->{created_on_formatted}
                = format_ts( MT::App::CMS::LISTING_DATE_FORMAT(),
                $ts, $blog, $lang );
            $row->{created_on_time_formatted}
                = format_ts( MT::App::CMS::LISTING_TIMESTAMP_FORMAT(),
                $ts, $blog, $lang );
            $row->{created_on_relative} = relative_date( $ts, time, $blog );
        }
        if ( $row->{created_by} ) {
            my $created_user = $users{ $row->{created_by} }
                ||= MT::Author->load( $row->{created_by} );
            if ($created_user) {
                $row->{created_by} = $created_user->nickname;
            }
            else {
                $row->{created_by} = $app->translate('(user deleted)');
            }
        }
        my $revision    = $obj->object_from_revision($rev);
        my $column_defs = $obj->column_defs;

        #my @changed = map {
        #    my $label = $column_defs->{$_}->{label};
        #    $label ||= $_;
        #    $app->translate( $label );
        #} @{ $revision->[1] };
        #$row->{changed_columns} = \@changed;
        if ( ( 'entry' eq $type ) || ( 'page' eq $type ) ) {
            $row->{rev_status} = $revision->[0]->status;
        }
        $row->{rev_js}     = $js . '&amp;r=' . $row->{rev_number} . "'";
        $row->{is_current} = $param->{revision} == $row->{rev_number};
    };
    return $app->listing(
        {   type   => "$type:revision",
            code   => $hasher,
            terms  => { $class->datasource . '_id' => $obj->id },
            source => $type,
            params => { dialog => scalar $q->param('dialog'), },
            %$param
        }
    );
}

sub list_revision {
    my $app   = shift;
    my $q     = $app->param;
    my $type  = $q->param('_type');
    my $class = $app->model($type);
    my $id    = $q->param('id');
    my $rn    = $q->param('r');

    $id =~ s/\D//g;
    my $obj = $class->load($id)
        or return $app->error(
        $app->translate(
            'Can\'t load [_1] #[_1].', $class->class_label, $id
        )
        );
    my $blog = $obj->blog || MT::Blog->load( $q->param('blog_id') ) || undef;
    my $author = $app->user;
    return $app->permission_denied()
        if $type eq 'entry'
        ? (     $obj->author_id == $author->id
                ? !$app->can_do('edit_own_entry')
                : !$app->can_do('edit_all_entries')
            )
        : $type eq 'page'     ? !$app->can_do('edit_all_pages')
        : $type eq 'template' ? !$app->can_do('edit_templates')
        : 0;

    my $js
        = "parent.location.href='"
        . $app->uri
        . '?__mode=view&amp;_type='
        . $type
        . '&amp;id='
        . $obj->id;
    if ( defined $blog ) {
        $js .= '&amp;blog_id=' . $blog->id;
    }
    my $revision = $rn
        || (
          $obj->has_meta('revision')
        ? $obj->revision || $obj->current_revision
        : $obj->current_revision
        || 0
        );
    return build_revision_table(
        $app,
        object => $obj,
        param  => {
            template => 'dialog/list_revision.tmpl',
            args     => {
                sort_order => 'rev_number',
                direction  => 'descend',
            },
            rev_js   => $js,
            revision => $revision,
        }
    );
}

sub save_snapshot {
    my $app   = shift;
    my $q     = $app->param;
    my $type  = $q->param('_type');
    my $id    = $q->param('id');
    my $param = {};

    return $app->errtrans("Invalid request.")
        unless $type;

    $app->validate_magic() or return;

    $app->run_callbacks( 'cms_save_permission_filter.' . "$type:revision",
        $app, $id )
        || return $app->error(
        $app->translate( "Permission denied: [_1]", $app->errstr() ) );

    my $filter_result
        = $app->run_callbacks( 'cms_save_filter.' . "$type:revision", $app );
    if ( !$filter_result ) {
        my %param = (%$param);
        $param{error}       = $app->errstr;
        $param{return_args} = $app->param('return_args');
        my $mode = 'view_' . $type;
        if ( $app->handlers_for_mode($mode) ) {
            return $app->forward( $mode, \%param );
        }
        return $app->forward( 'view', \%param );
    }

    my $class = $app->model($type)
        or return $app->errtrans( "Invalid type [_1]", $type );
    my $obj;
    if ($id) {
        $obj = $class->load($id)
            or
            return $app->error( $app->translate( "Invalid ID [_1]", $id ) );
    }
    else {
        $obj = $class->new;
    }

    my $original = $obj->clone();
    my $names    = $obj->column_names;
    my %values   = map { $_ => ( scalar $q->param($_) ) } @$names;

    if ( ( 'entry' eq $type ) || ( 'page' eq $type ) ) {
        $app->_translate_naughty_words($obj);
    }
    delete $values{'id'} if exists( $values{'id'} ) && !$values{'id'};
    $obj->set_values( \%values );
    unless (
        $app->run_callbacks(
            'cms_pre_save.' . "$type:revision",
            $app, $obj, undef
        )
        )
    {
        $param->{return_args} = $app->param('return_args');
        return edit(
            $app,
            {   %$param,
                error => $app->translate(
                    "Saving snapshot failed: [_1]",
                    $app->errstr
                )
            }
        );
    }
    $obj->gather_changed_cols($original);
    if ( exists $obj->{changed_revisioned_cols} ) {
        my $col = 'max_revisions_' . $obj->datasource;
        if ( my $blog = $obj->blog ) {
            my $max = $blog->$col;
            $obj->handle_max_revisions($max);
        }
        my $revision = $obj->save_revision( $q->param('revision-note') );
        $app->add_return_arg( r => $revision );
        if ($id) {
            my $obj_revision = $original->revision || 0;
            unless ($obj_revision) {
                $original->revision( $revision - 1 );

                # hack to bypass instance save method
                $original->{__meta}->save;
            }
            $original->current_revision($revision);

            # call update to bypass instance save method
            $original->update or return $original->error( $original->errstr );
        }

        $app->run_callbacks( 'cms_post_save.' . "$type:revision",
            $app, $obj, undef )
            or return $app->error( $app->errstr() );

        $app->add_return_arg( 'saved_snapshot' => 1 );
    }
    else {
        $app->add_return_arg( 'no_snapshot' => 1 );
    }

    $app->add_return_arg( 'id' => $obj->id ) if !$original->id;
    $app->call_return;
}

sub empty_dialog {
    my $app = shift;
    $app->build_page('dialog/empty_dialog.tmpl');
}

1;
